The use of satellite-based navigation in satellite-based navigation devices is becoming more and more prevalent. Many vehicle operators rely solely on such navigation devices to provide them with turn-by-turn directions to reach their intended destinations. However, map conditions and address information are subject to changes, as some roads are added and others are removed, as well as with the opening and closing of various businesses. And, given the enormous amount of map-related data available, keeping the map information up-to-date in a vehicle and/or on a navigation device is a difficult task.
Many systems generally rely on a user to update the maps stored locally at a navigation device, for example, on an annual basis, by securely transferring map data from a computer-readable medium to the navigation device. One conventional way of transferring the data is via a Universal Serial Bus (USB) connection. Another way is to insert one or more DVD-ROMs containing the map data into an optical drive and read the data from the optical drive.
Because this map data includes a large amount of information and may be made up of thousands of files, this process can take a very long time, and it is inconvenient for a user to keep the navigation device continuously powered on for the amount of time required for updating the maps (which may take hours). This is especially problematic for a navigation device of a vehicle, as the vehicle is required to remain on. Additionally, if the update is interrupted, for example, by the navigation device powering off or the map data source being disconnected (either inadvertently or intentionally), the update process must start over from the beginning. This is to ensure that the update package for map data is authentic, from a trusted source, and has not been tampered with.